<button type="button" class="btn btn-default form-control ui-select-match"
        ng-hide="$select.open"
        ng-disabled="$select.disabled"
        ng-click="$select.activate()">
  <span ng-hide="$select.selected !== undefined" class="text-muted">{{$select.placeholder}}</span>
  <span ng-show="$select.selected !== undefined" ng-transclude></span>
  <span class="caret"></span>
</button>
